I have a 2003 Navigator with 194k miles. I need some help thinking about solutions to this stalling issue. While driving, all is fine, then bam, all is off. Sometimes when I idle, it rumbles and is kinda rough. I have cleaned my MAF sensor, replaced cam shaft and crank shaft sensors a year ago, replaced idle air control valve a year ago, changed fuel filter 6-months ago, still not fixed the issue. I have the original PVC valve, and oxygen sensors in the vehicle. Just can't figure this out. When it shuts off it starts right back up, lucky for us. It died three times on the way to school today. Not good.

I would appreciate any help or suggestions. Thank y'all.

 

There are literally dozens of different things that can cause this, so any suggestion is nothing but a shot-in-the-dark. The first thing to try though is the wiggle test. Start the engine and then begin wiggling everything in sight, starting with the ECM and battery connectors.

 

I had 3 different coils do that same exact scenario every time 1 went bad.

 

Ok. Since I was in a crunch, I pushed forward with quick action. I cleaned the Idle Air Control Valve with some throttle body cleaning solvent, next I did the same with the PVC valve, and the Mass Air Flow Sensor. I replaced two oxygen sensors. Status now: it will run with out stalling, but still seems to be idling a little rough. I ordered a new IAC and PVC valve from Ford. If that still does not get it done, I am just going to fully replace the MAF sensor.

It really feels like a combustion issue somehow. I recently replaced all 8 spark plugs and COP for the car. They have less than 10k miles on them.

I really have no way to test parts, but I can sure clean and change. Just wish I could smooth out this idle.

Here is a question, we idle the car for long periods of time, what issues can be created that may result in some of our problems?

Thanks y'all . . .

 

Any check engine lights? Might be experiencing a vacuum leak.

 

Ok. Update. I bought a new IAC valve from Ford and I am very certain it was manufactured by the same company and the one I bought from Advanced Auto Parts a year ago. Anyway, installed it and also installed a new PVC valve assembly with hoses and 90's from Ford. It was a stock part which tells me it must have some common failures. My wife is gonna drive it again tomorrow and let me know if there is any other issues. Best way to find out is try it! I will let you know.

 

Final update: I discovered that I had a broken EGR Pressure Sensor (F77E-9J460-AB). The post holding the tubing was broken completely off. I went down to Advanced and pick up a new one to install it. I now have a smooth idle and it is not shutting off. I am thankful for the fourm because I read another post where another owner found the same problem, even though he was getting slightly different codes. Till next time.

 

I had similar issues and it turned out to be a pretty comon issue with the fuel pump relay. Check out the following forum for details - Sparky's Answers: 2003 Ford Expedition, No Run, No Fuel Pump Operation, Code P0231

Worked like a dream for me - $3.90 for a replacement relay at Digikey. You must be handy with a soldering iron, as the relay is mounted on the Fuse/Relay Block printed circuit board (PCB).

Enjoy!

 

I am having random stalling issues with our 2003 expedition. It has happened while driving, starts back up after a few seconds wait or couple of quick attempts. It then will run fine for a while. It does not show any code or warning light. In last 6 months have replaced battery, pcv valve, and plugs and coils about a year ago. I have cleaned the MAF, throttle body, battery connections and had Autozone check alternator/battery.
Could the Idle Air Control Valve cause such a problem? I have ordered a new one, tried to remove and clean the old one, but having problem removing bolt so far. You also need ob/gyn hands to get to it!!!!

 

The IAC valve is only in play at idle. So if the stalling happens when your foot is on the gas pedal then the IAC valve is not the problem.

 

Thanks Alloro. I put a new fuel filter on earlier this year, could it be related to the fuel pump? Should I expect an error code or light if it was the pump? Any other thoughts?

 

This is the precise issue I was having and it turned out to be fuel pump relay - it was burnt out, causing an intermittent problem. Solved the 'stalling while driving issue', but not the rough idling - replaced the coils, plugs, fuel filter, cleaned the IAC valve, cleaned the PCV valve, etc. Going through the fuel additive cleaning process, which I don't think will work, but it's an easy one to do. Check out my earlier post on the relay problem, which may be related to a problem with the fuel pump that could have caused the relay to burn out (yet to be verified at a later time)...

 

Is there a test to confirm or do I need to pull out the internal fuse panel to view?
There are no error codes showing so far, do you have one? I am entering new territory with anything beyond basic car maintenance, so I really appreciate your help.

 

Ok team, let me wrap up my issues on the navigator. I read the posting "sparky's answers" and he was right on. I set to the dealership and bought the junction fuse box complete with power cable. It came in today and I installed it, right in about 30 minutes and paid $320 from Ford for the part. That relay in the board is an issue. No doubly about it. Mine fired right up after installed the new junction fuse box. I have a Lincoln manufactured in Jan 2003 which takes a different box than ones made in Feb 2003 and later. It was so smooth I was scared it would not work. I just unplugged a few connections, pulled the box, disconnected it from the battery lead and pulled it all out. I owe a big thanks to those who brought up this relay issue. It is a true failure point. I pulled a secondary trouble code on the computer just prior to committing to big the board, and when the code was "P0231 Fuel Pump Secondary Circuit Low" I knew I had the same problem described by Sparky. This code does not throw a check engine light, but can be pulled with a quality code scanner which looks at Ford products.

Sparky's Answers: 2003 Ford Expedition, No Run, No Fuel Pump Operation, Code P0231

 

You need to pull the secondary computer codes and see what you get. Your primary check engine light code will show nothing. However, a quality scanner will let you read continuous or detailed computer codes deep in the PCM. My first scan showed zippo. I found a setting in the scanner to pull detailed or advanced secondary codes and that is when it showed up. It was a $500 scanner deposit, and it was specialized to Ford and Mazda vehicles.

I was amazed. Really. This was a tota faith effort in what was posted on this fourm, and it paid off. Navigator is rolling again.

Hope this helps.